Dissertations / Theses on the topic 'Local buckling'
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Hakmi, M. R. "Local buckling of sandwich panels." Thesis, University of Salford, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234622.
Full textClarin, Mattias. "Plate buckling resistance : patch loading of longitudinally stiffened webs and local buckling /." Luleå : Division of Structural Engineering - Steel Structures, Department of Civil, Mining and Environmental Engineering, Luleå University of Technology, 2007. http://epubl.ltu.se/1402-1544/2007/31/LTU-DT-0731-SE.pdf.
Full textYoon, Soon Jong. "Local buckling of pultruded I-shape columns." Diss., Georgia Institute of Technology, 1993. http://hdl.handle.net/1853/20118.
Full textDa, Silva Vellasco Pedro Colmar Goncalves. "Local web buckling in tapered composite beams." Thesis, Imperial College London, 1992. http://hdl.handle.net/10044/1/29499.
Full textGhosh, Biswarup. "Consequences of Simultaneous Local and Overall Buckling in Stiffened Panels." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/31803.
Full textMaster of Science
Clarin, Mattias. "High strength steel : local buckling and residual stresses." Licentiate thesis, Luleå, 2004. http://epubl.luth.se/1402-1757/2004/054.
Full textBonanni, David L. "Local buckling and crippling of composite stiffener sections." Thesis, Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/80050.
Full textMaster of Science
Dardano, Nicola. "Delamination of thin layers promoted by local buckling." Thesis, IMT Alti Studi Lucca, 2022. http://e-theses.imtlucca.it/363/1/Dardano_phdthesis.pdf.
Full textBecque, Jurgen. "The interaction of local and overall buckling of cold-formed stainless steel columns." Thesis, The University of Sydney, 2008. http://hdl.handle.net/2123/3772.
Full textBecque, Jurgen. "The interaction of local and overall buckling of cold-formed stainless steel columns." University of Sydney, 2008. http://hdl.handle.net/2123/3772.
Full textAbstract: The objective of this research is to investigate the interaction of local and overall flexural buckling in cold-formed stainless steel columns. Literature study exposes a lack of understanding of this subject and a need for experimental data, particularly on the local-overall interaction buckling of stainless steel open sections. Two separate experimental programs were therefore carried out. The first program included 36 tests on pin-ended lipped channel columns. Three alloys were considered: AISI 304, AISI 430 and 3Cr12. The specimens were designed to fail by local-overall interaction buckling in the inelastic stress range, thus highlighting the non-linear behaviour of stainless steel. Half of the specimens were tested under a concentric load. The other half had the load applied with a nominal eccentricity of Le/1500. The test results demonstrate the imperfection sensitivity of local-overall interaction buckling and illustrate the shift in effective centroid in pin-ended columns with singly symmetric cross-section. The second experimental program studied local-overall interaction buckling in 24 pin-ended stainless steel I-section columns. The specimens consisted of plain channels connected back-to-back using sheet metal screws. Two alloys were considered: AISI 304 and AISI 404. Local and overall imperfections were carefully measured in both experimental programs. Extensive material testing was carried out on the alloys employed in the experimental program, in order to determine tensile and compressive material properties, anisotropic parameters and enhanced corner properties. A detailed finite element model is presented, which includes non-linear material behaviour, anisotropy, increased material properties of the corner areas and local and overall imperfections. The model was verified against the two aforementioned experimental programs and against additional data available in literature on stainless steel SHS columns. The model yielded excellent predictions of the specimen failure mode, ultimate strength and load-deformation behaviour. The finite element model was used to generate additional data for stainless steel columns with lipped channel, plain channel, SHS and I-shaped cross-section, failing by local-overall interaction buckling. The parametric studies covered the practical ranges of overall and cross-sectional slenderness values. The Australian/New Zealand, European and North American standards for stainless steel were evaluated using the available data. The comparison reveals an inability of the design codes to properly account for the interaction effect as the cross-sectional slenderness increases. Predictions are unsafe for I-section columns with intermediate or high cross-sectional slenderness. A direct strength method is proposed for stainless steel columns, accounting for the local-overall interaction effect. The method offers a simple design solution which fits within the framework of the current Australian and North-American standards.
Bock, Montero Marina. "Web crippling and local buckling response of stainless steel sections." Doctoral thesis, Universitat Politècnica de Catalunya, 2015. http://hdl.handle.net/10803/285582.
Full textEsta tesis estudia la respuesta estructural de elementos de acero inoxidable sometidos a fuerzas transversales i normales que desencadenan los fenómenos de inestabilidad llamados web crippling y local buckling, respectivamente. Actualmente, la parte de Eurocódigo que contempla los aceros inoxidables, el EN 1993-1-4 (2006) carece de ecuaciones de diseño para web crippling y la aplicabilidad de algunas de sus especificaciones necesita ser validada especialmente para los aceros inoxidables ferríticos. La primera parte de esta tesis se focaliza en el desarrollo de ecuaciones de diseño para el tratamiento del web crippling en secciones de acero inoxidable que actualmente se diseñan siguiendo las especificaciones dadas en EN 1993-1-3 (2006) para acero al carbono conformado en frío. Dos métodos de diseño para los aceros inoxidables austeníticos y ferríticos: una ecuación empírica en línea con la actual dada en EN 1993-1-3 (2006); y un método de diseño semi-empírico basado en curvas de resistencia que permite entender mejor el fenómeno y muestra una mejora importante de las predicciones a web crippling. Para la segunda parte de la tesis, se ha estudiado la aplicabilidad de las actuales especificaciones para el diseño a local buckling dadas en EN 1993-1-4 (2006) a los aceros inoxidables ferríticos focalizándose en los límites de esbeltez y las ecuaciones de ancho eficaz. Los resultados mostraron que EN 1993-1-4 (2006) puede ser aplicado a los aceros inoxidables ferríticos, aunque el código es bastante conservador en comparación con otros métodos de diseño. Finalmente, se propuso una modificación de la ecuación del ancho eficaz que incorpora la interacción entre los elementos de la misma sección y que permite, además de mejorar las predicciones de la resistencia seccional, llevar el método del ancho eficaz hasta el mismo nivel que otros métodos de diseño pero ensalzando el uso de los conceptos actualmente considerados en Eurocódigo
Jeevaharan, Manohara. "Local buckling behaviour and design of sandwich panels in buildings." Thesis, Queensland University of Technology, 1997. https://eprints.qut.edu.au/35998/1/35998_Jeevaharan_1997.pdf.
Full textChung, Kwok Fai. "The elastic distortional and local plate buckling of slender web beam." Thesis, Imperial College London, 1988. http://hdl.handle.net/10044/1/7860.
Full textMyrholm, Brian W. "Local buckling and fracture behaviour of line pipe under cyclic loading." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ60477.pdf.
Full textKandil, Kamel Sayed Ahmed. "Interaction between local and Euler buckling modes in thin-walled columns." Thesis, University of Cambridge, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.254398.
Full textZainal, Abidin Ahmad Razin. "Modelling of local elastic buckling for steel beams with web openings." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/12789.
Full textMasri, Haji Mohammad Khairul Ja'afar Awang Haji. "Elastic properties and local buckling of pultruded fibre reinforced plastic profiles." Thesis, Cardiff University, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.548179.
Full textSlyh, Caleb E. "Investigation into POR-14-0630 Bridge Pile Failures." Ohio University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1553874013897449.
Full textSmith, Frank Harrison. "Elastic buckling solutions for thin-walled metal columns with perforation patterns." Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/23680.
Full textMaster of Science
Seresta, Omprakash. "Buckling, Flutter, and Postbuckling Optimization of Composite Structures." Diss., Virginia Tech, 2007. http://hdl.handle.net/10919/26401.
Full textPh. D.
Kusyilmaz, Ahmet. "Finite Element Study On Local Buckling And Energy Dissipation Of Seismic Bracing." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12609662/index.pdf.
Full texthowever, it is now possible to conduct finite element simulation of brace components using personal computers. A finite element study has been undertaken to evaluate the aforementioned limits for pin-ended pipe section steel braces. Fifty four tubular pipe brace models possessing different diameter-to-thickness ratios varying from 5 to 30 and slenderness ratios varying from 40 to 200 were analyzed. The effect of cyclic hardening modulus on the response of braces was explored. In all analysis, the models were subjected to reversed cyclic displacements up to ten times the yield displacement. Local buckling was traced during the loading history using a criterion based on local strains. Results are presented in terms of the ductility level attained by the member at the onset of local buckling. It is shown that local buckling of the section is influenced by the diameter-to-thickness and the slenderness ratios of the member. Moreover, the amount of hardening modulus was found to affect the local buckling response significantly. The need to include this material property into seismic provisions is demonstrated. Finally, the hysteretic energy dissipated by the member was quantified for each displacement excursion.
Vakiener, Adam R. "Preliminary investigation of flange local buckling in pultruded wide flange structural shapes." Thesis, Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/19562.
Full textOLIVEIRA, JULIA PITHAN DE. "DESIGN EQUATIONS FOR LOCAL BUCKLING OF CASTELLATED BEAMS SUBJECTED TO PURE BENDING." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2017. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=36634@1.
Full textCOORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
PROGRAMA DE EXCELENCIA ACADEMICA
A motivação para este trabalho é desenvolver equações simples, porém suficientemente precisas, que possam ser usadas para projetos de vigas casteladas submetidas à flexão pura, considerando a contribuição do conjunto mesa-alma na flambagem local do elemento. Métodos energéticos - Quociente Rayleigh - são adotados para determinar a equação da tensão crítica aproximada. Neste método, a energia de deformação e o trabalho externo são calculados assumindo uma forma de deflexão aproximada, cinemática admissível e contínua. Assim, a precisão do resultado depende da qualidade da forma de deflexão adotada. Estas funções de forma foram escolhidas com base nos resultados obtidos a partir de modelos numéricos criados usando o software ABAQUS e verificados com o software GBTUL, considerando para analise a interação completa entre a alma e a mesa. As expressões desenvolvidas foram baseadas em aproximações clássicas de estabilidade de placas, validadas com estudos paramétricos realizados com os softwares ABAQUS e GBTUL. Os resultados indicaram que a equação proposta pode efetivamente calcular a tensão crítica relativa a instabilidade local de vigas casteladas. A expressão validada e os limites associados são destinados a ser gerais dentro dos limites típicos das aplicações práticas.
The motivation for this work is to develop a simple yet sufficiently accurate equation that can be used in the design of castellated beams subjected to pure bending, considering the contribution of the web-flange coupling effect in the local buckling. To accomplish this, an energy method - Rayleigh quotient - is adopted to determine the approximate critical stress equation. In this method, the strain energy and the potential work are calculated for an assumed approximate and kinematically admissible continuous deflected shape. Thus, the accuracy of the result is dependent on the quality of the assumed buckled shape. These shape functions were chosen based on the results obtained from numerical models created using ABAQUS software and verified with GBTUL, considering full interaction between web and flange. The developed closed-form expressions were based on classical plate stability approximations, validated with parametric studies performed using ABAQUS and GBTUL. The results indicate that the proposed equation can effectively calculate the critical stress of castellated beams due to local instability. The validated expression and its associated limits are intended to be general within the typical limits of practical applications.
Cai, Minjie. "Buckling strength of steel thin cylindrical shells under elevated local axial compression." Thesis, University of Edinburgh, 2003. http://hdl.handle.net/1842/10848.
Full textHaidarali, Mohammad Reza. "Local and distortional buckling behaviour of cold-formed steel Z section beams." Thesis, Imperial College London, 2011. http://hdl.handle.net/10044/1/6992.
Full textShin, Youngwon. "Analytic shape sensitivities and approximations of local and global airframe buckling constraints /." Thesis, Connect to this title online; UW restricted, 1997. http://hdl.handle.net/1773/9984.
Full textQin, Yi. "Numerical analysis of inelastic local web buckling capacity of coped steel I-beam." Thesis, University of Macau, 2012. http://umaclib3.umac.mo/record=b2586272.
Full textToneff, Janine Diana. "Local and overall buckling of thin-walled beams and columns using finite elements." Thesis, University of British Columbia, 1986. http://hdl.handle.net/2429/26334.
Full textApplied Science, Faculty of
Civil Engineering, Department of
Graduate
Nassirirad, Arash. "The effects of corner radii on the local buckling of cold-formed sections." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0003/MQ39469.pdf.
Full textChen, Yi 1975. "Local buckling behaviour of pultruded FRP composite sheet piles subjected to uniform pressure." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=98950.
Full textThe local buckling of the compressive flanges was monitored by the strain measurements, which demonstrated that when tested in upright position, the panel failed immediately after local buckling of compressive flange, and when tested in inverted position, the panels could be able to carry the load into post buckling region. The stresses and corresponding axial forces at buckling were calculated by the classical beam flexure formula but taking into consideration the reduction of flexure rigidity and neutral axis shifting. The axial force calculated from the beam flexure formula was comparable with that from stain gauge measurements. The axial force was not uniformly distributed along the width of the compressive flange at upright position and was about zero at the free edge. When tested in inverted position, the neutral axis distance and the flexure rigidity kept almost as a constant. The sheet pile panels were with a uniform axial force along the width of the compressive flange.
An analytical modeling was performed to predict the buckling initiation. The buckling of the panel was simplified as the buckling of the compressive flange with various boundary conditions. The differential equation of the compressive flange was established based on the assumption that the flange was subjected to an in-plane axial force and an out-of-plane lateral pressure simultaneously. It was found that the lateral pressure did not have direct effect on the critical load. It was the compressive axial force that determined the local buckling of the flange. Kollar's explicit expressions were also applied but only valid for long plate loaded by uniform axial force.
The buckling load obtained by solving the differential equation for the inverted panel compared well with that from the experimental results. However, for the flange in a pile at an upright position, the theoretical prediction was far less than the experimental value which might be attributed to the non uniform axial force on the flange. Energy method was applied to estimate the range of the buckling load of a plate loaded by a linearly distributed axial force. The upper bound value was obtained from fixed boundary condition and the lower bound from simply supported assumption. The experimental result was found in between the two bounds and was in favour of the lower bound as a conservative estimation of critical load for upright panel.
CINTRA, GISELE GOES. "LOCAL BUCKLING BEHAVIOR OF PULTRUDED GLASS-FIBER REINFORCED POLYMER (PGFRP) I-SECTION COLUMNS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2017. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=36745@1.
Full textCOORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
PROGRAMA DE EXCELENCIA ACADEMICA
Este trabalho tem como objetivo investigar o desempenho de colunas com seção I em polímeros reforçados com fibra de vidro (pGFRP) submetidas a cargas de compressão concêntricas de curta duração. Uma revisão bibliográfica acerca das teorias existentes é apresentada, incluindo os conceitos básicos de instabilidade, teoria de flambagem global e local, modos de falha de colunas perfeitas, bem como o comportamento de colunas reais. Um programa experimental foi conduzido, incluindo a caracterização dos materiais. Vinte e nova colunas – com três diferentes seções I e diferentes tipos de resina, propriedades mecânicas, bem como comprimentos – foram testadas. Do ponto de vista global, as colunas foram biengastadas. As placas constituintes, por sua vez, foram testadas com três diferentes condições de contorno: biengastadas (CC), biapoiadas (SS) e simplesmente em contato com as chapas de base da máquina de compressão (CB). Foi observado que a condição de contorno CB – a mais adotada em estudos anteriores -, se aproxima mais de um engaste do que de uma condição simplesmente apoiada. A distribuição não linear de deformações elásticas ao longo da seção também foi investigada. Finalmente, recomendações para um ensaio de flambagem local apropriado foram propostas.
This work aims to investigate the performance of pultruded glass fiber reinforced polymer (pGFRP) I-section columns subject to short term concentric compression. A review of existing theories is presented, including the instability concepts, global and local buckling theories, perfect columns failure modes and the behavior of real columns. An experimental program including material characterization was conducted. Twenty-nine stubs – with three different I-sections geometries, having distinct flange width-to-section depth ratios (bf/d = 0.5; 0.75 and 1.0), mechanical properties, overall lengths and matrices – were tested. In a global point of view, the columns were fixed at both ends. The constituent plates, on the other hand, were tested with different end-conditions: clamped (CC), simply supported (SS) and simply in contact with base plates of the universal machine (CB). The third analyzed boundary condition, which is the most adopted in previous studies, was concluded to be closer to a clamped end-condition. The non-linear elastic strains distribution throughout the cross-section was also investigated. Finally, guideline recommendations for successful local buckling tests were proposed.
Ovesy, H. R. "The development and application of a semi-energy post-local buckling finite strip." Thesis, Cranfield University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.742420.
Full textYap, Derrick. "Interaction of local and distortional buckling of high strength cold-formed steel columns." Thesis, The University of Sydney, 2008. https://hdl.handle.net/2123/28965.
Full textSchillo, Nicole [Verfasser]. "Local and global buckling of box columns made of high strength steel / Nicole Schillo." Aachen : Shaker, 2017. http://d-nb.info/1138177393/34.
Full textPokharel, Narayan. "Behaviour and design of sandwich panels subject to local buckling and flexural wrinkling effects." Thesis, Queensland University of Technology, 2003. https://eprints.qut.edu.au/15890/1/Narayan_Pokharel_Thesis.pdf.
Full textPokharel, Narayan. "Behaviour and Design of Sandwich Panels Subject to Local Buckling and Flexural Wrinkling Effects." Queensland University of Technology, 2003. http://eprints.qut.edu.au/15890/.
Full textLee, Jung Hoon. "Local buckling behaviour and design of cold-formed steel compression members at elevated temperatures." Thesis, Queensland University of Technology, 2004. https://eprints.qut.edu.au/15972/1/Jung_Hoon_Lee_Thesis.pdf.
Full textLee, Jung Hoon. "Local buckling behaviour and design of cold-formed steel compression members at elevated temperatures." Queensland University of Technology, 2004. http://eprints.qut.edu.au/15972/.
Full textFagerberg, Linus. "Wrinkling of sandwich panels for marine applications." Doctoral thesis, KTH, Aeronautical and Vehicle Engineering, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3587.
Full textThe recent development in the marine industry with largerships built in sandwich construction and also the use of moreadvanced materials has enforced improvements of design criteriaregarding wrinkling. The commonly used Hoffs formula isnot suited for the highly anisotropic fibre reinforced sandwichface sheets of today.
The work presented herein investigates the wrinklingphenomenon. A solution to wrinkling of anisotropic sandwichplates subjected to multi-axial loading is presented. Thesolution includes the possibility of skew wrinkling where thewrinkling waves are not perpendicular to the principal loaddirection. The wrinkling angle is obtained from the solutiontogether with the maximum wrinkling load. This method has beensupported with tests of anisotropic plates subjected touni-axial and bi-axial loading.
The effect of the face sheet local bending stiffness showsthe importance of including the face sheet stacking sequence inthe wrinkling analysis. The work points out the influence ofthe face sheet local bending stiffness on wrinkling. Threedifferent means of improving the wrinkling load except changingcore material is evaluated. The effect of the differentapproaches is evaluated theoretically and also throughcomparative testing. The transition between wrinkling and pureface sheet compression failure is investigated. Theoreticaldiscussions are compared with compressive test results of twodifferent face sheet types on seven different core densities.The failure modes are investigated using fractography. Theresults clearly show how the actual sandwich compressionfailure mode is influenced by the choice of core material,changing from wrinkling failure to face sheet micro bucklingfailure as the modulus density increases.
Finally, a new approach is presented where the wrinklingproblem is transferred from a pure stability problem to amaterial strength criterion. The developed theory providesmeans on how to decide which sandwich constituent will failfirst and at which load it will fail. The method give insightto and develop the overall understanding of the wrinklingphenomenon. A very good correlation is found when the developedtheory is compared with both finite element calculations and toexperimental tests.
Keywords:wrinkling, local buckling, imperfection,stability, anisotropy, sandwich
Huynh, Le Anh Thi. "Strength and Behaviour of Cold-rolled Aluminium Sections." Thesis, The University of Sydney, 2019. https://hdl.handle.net/2123/21549.
Full textMysore, Paramesh Pragati. "Feasibility Study on Highly Slender Circular Concrete Filled Tubes Under Axial Compression." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/75045.
Full textMaster of Science
Mahenthirarasa, Rokilan. "Cold-formed steel compression members exposed to extreme temperature environments." Thesis, Queensland University of Technology, 2021. https://eprints.qut.edu.au/226125/1/Rokilan_Mahenthirarasa_Thesis.pdf.
Full textSchillo, Nicole Verfasser], Markus [Akademischer Betreuer] [Feldmann, and Andreas [Akademischer Betreuer] Taras. "Local and global buckling of box columns made of high strength steel / Nicole Schillo ; Markus Feldmann, Andreas Taras." Aachen : Universitätsbibliothek der RWTH Aachen, 2017. http://d-nb.info/1162499257/34.
Full textSchillo, Nicole [Verfasser], Markus [Akademischer Betreuer] Feldmann, and Andreas [Akademischer Betreuer] Taras. "Local and global buckling of box columns made of high strength steel / Nicole Schillo ; Markus Feldmann, Andreas Taras." Aachen : Universitätsbibliothek der RWTH Aachen, 2017. http://nbn-resolving.de/urn:nbn:de:101:1-2018071007084306056654.
Full textNuttayasakul, Nuthaporn. "Experimental and Analytical Studies of the Behavior of Cold-Formed Steel Roof Truss Elements." Diss., Virginia Tech, 2005. http://hdl.handle.net/10919/29765.
Full textPh. D.
YANG, Demao. "Compression Stability of High Strength Steel Sections with Low Strain-Hardening." University of Sydney. School of Civil Engineering, 2003. http://hdl.handle.net/2123/561.
Full textAmarante, Rodrigo de Almeida. "Compressão dinâmica em risers." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/3/3135/tde-11082015-154505/.
Full textThis work was carried out through a threefold approach to dynamic compression in risers, based on tests in a Hydrodynamic Calibrator, with subsequent comparison of results with analytical formulations and the use of commercial softwares dedicated to the study of static and dynamic flexible lines. The main aim was an accurate determination, from a minimally invasive instrumentation, the lengths of flexural waves generated in the TDP, during dynamic compression. This goal, in itself, is the novelty of this thesis. The tests consisted in performing circular motion on top of a flexible catenary model launched under several conditions, amounting to a total of 72 experiments: three motion frequencies, three imposed amplitudes , four top angles and clockwise and counter-clockwise rotation. A tracking monitoring system was used as main instrumentation. In such equipment, a load cell was used, positioned between rotor used to prescribe top movements at the top of a flexible model, allowing the load cell jointly move around a bar conected to the shaft motor. Numerical routines, made by author, were used for data post-processing. The results were then confronted with analytical formulations from specialized literature, as well as the adaptation of the equation for the buckling critical load for curved beams under the boundary conditions of the tests. As a main result, it is possible to mention the experimental confirmation of the current assumption with respect to the wave number associated with bending waves generated during the dynamic compression, hitherto assumed as an ad hoc hypothesis. In addition, the procedure adopted, based in analytical theories, was used since the establishment of the material with which the model is built, through the rational development of the test matrix and ending with the analyzes carried out when the experimental results were compared with analytical predictions.
Cheng, Shanshan. "Fire performance of cold-formed steel sections." Thesis, University of Plymouth, 2015. http://hdl.handle.net/10026.1/3316.
Full textPerera, Nilakshi. "Structural behaviour and design of innovative hollow flange steel plate grinders." Thesis, Queensland University of Technology, 2018. https://eprints.qut.edu.au/123310/1/Liyanage%20Nilakshi%20Piyahasi_Perera_Thesis.pdf.
Full textNguyen, The Nguyen. "Flambage sous contact d’une coque cylindrique soumise à pression externe." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEI070/document.
Full textMotivated by practical engineering applications, thin-walled cylindrical shells are widely used as structural elements. Because of their low flexural strength, these structures are very sensitive to buckling when exposed to external pressur. Conventional stiffening which makes it possible to improve the bearing capacity is to add stiffening rings connected by axial stiffeners or axial stiffeners. In these configurations the stiffening elements are an integral part of the structure with a continuity of material. One can ask the question of the effect of contiguous but non-continuous adjacent external structures ensuring total or local surface external contact. These are real configurations, such as those of buried pipelines, pipelines, or the case of insulated structures. This study aims to analyze these cases where the shell is in contact with a material which confines it, and that it undergoes an external lateral pressure. The contact conditions between the two bodies, whether rubbing or not, the stiffness of the confinement as well as the loading conditions, the pressure which can be directly applied to the shell as it may be induced by the confinement material which by withdrawal or shrinkage or Radial convergence induces stresses, these are the parameters that we consider essential for gauging the problem of buckling with contact of an external pressure shell. To answer these questions, we conducted an experimental campaign where several configurations of confinement are considered. The nature of the external environment associated with the confinement and therefore its rigidity, the type of confinement, discrete local or the total property (entire surface of the shell), are evaluated. Appropriate instrumentation, coupling point and field measurements, has allowed us to correctly highlight the phenomenology. Numerical modeling is also carried out using finite element method by Abaqus/Standard 6.12-3 code. Numerical simulations integrate the different nonlinearities in this problem, large displacements and rotations due to buckling, nonlinearity material, in some cases the buckling is plastic, but also the nonlinearity induced by an evolutionary contact. The modeling is carried out in 2D and 3D mesh, and in the latter case either by means of shell elements or by massive elements, the first aim being to corroborate the experimental observations more or less precisely. This work shows that even for external confinement with very low membrane rigidity, as for sand or expanded polystyrene, a significant gain in bearing capacity is observed, the buckling is delayed. The increase is substantial in the case of a total confinement which is not negligible and consistent in the case of local confinement. We have also found that the buckling load and the associated mode depend on the contact configuration, in particular the flexural rigidity of the confinement